Tomas Mejias is leaving Middlesbrough for Dinamo Bucharest

Bettinelli is understood to have agreed the switch from Craven Cottage, although the deal is unlikely to go through until Fulham boss Scott Parker completes the signing of Alphonse Areola on loan from Paris St Germain.

Areola will compete with Marek Rodak for the number one spot at Fulham, leaving Bettinelli surplus to requirements.

Boro are willing to pay a six-figure loan fee to secure the services of the 28-year-old, who should arrive in time to be eligible for Friday’s opening Championship game at Watford.

A product of Fulham’s youth academy, Bettinelli has spent his entire career with the Cottagers, making a total of 120 senior appearances.

A former England Under-21 international, the shot-stopper was briefly called into Gareth Southgate senior England set-up in 2018, although he did not win a full cap.

He made 14 Championship appearances last season as Fulham won promotion to the Premier League, but spent the second half of the campaign restricted to the substitutes’ bench.

His arrival on Teesside is set to coincide with Mejias’ departure, with the Spaniard, who still has one more year of his current contract remaining, on the verge of a move to Dinamo Bucharest.

Mejias’ representatives have held talks with the Romanian club, and Mejias is expected to end his second spell as a Middlesbrough player shortly.

He might not be the only goalkeeper leaving this summer, as Bettinelli’s signing would also place a major question mark over the future of Aynsley Pears and Dejan Stojanovic.

The pair spent most of last season battling for Boro’s goalkeeping jersey, and the fact Neil Warnock played both in the final eight matches of the campaign suggests he is not especially convinced about either player. With Stojanovic having started last weekend’s Carabao Cup win over Shrewsbury Town, Pears is regarded as the likeliest to leave.

Meanwhile, Boro’s Carabao Cup second-round game with Barnsley will take place on Tuesday, September 15 (6pm).